In residential and commercial building construction it is necessary to connect the base of a toilet, usually made of porcelain or similar material, to a drain pipe in a secure and water tight manner that meets all plumbing codes applicable in the local jurisdiction. The most common way of achieving this connection is to utilize a closet or toilet flange. The conventional toilet flange (1; FIG. 1) has a generally flat upper surface 3 and round perimeter surface 4 and includes at least one pair of semi-circular diametrically opposed arcuate key-shaped slots 2 which extend circumferentially 10 and allow for the insertion of toilet fastening bolts (9; FIG. 3) that are used to tighten the base of the toilet to the flange. Some toilet flanges include opposed radially extending slots 5 which cause the toilet fastening bolts 9 to be at a fixed position circumferentially but provide a means of removing, and possibly replacing at a later date, the bolt 9 radially along the slots as seen in FIGS. 1-3. As seen in the top view of FIG. 3, a conventional toilet fastening bolt 9 has a base with a major axis formed with two opposed extensions 9L,9R. Since the bolts 9 slide readily along the respective slots, all the tension force along the fastening bolts at the time of toilet installation is transferred solely from the opposed extensions 9L,9R to the area on either side of the slots as seen in each of FIGS. 1-3. This creates a pair of concentrated force areas on the toilet flanges but also results in instability in keeping the toilet fastening bolts 9 erect during installation. A further problem is making sure the opposed extensions 9L,9R are in the proper rotational position to maximize the surface area interaction. Early toilet flanges were made of cast iron and were connected to cast iron drain pipes. Modern closet flanges are typically made of ABS or PVC plastic and include a main cylindrical body portion 6 or collar that is solvent welded to a drain pipe riser (not shown) of a similar plastic and an attachment flange portion 7 that extends radially from the upper end (11; FIG. 2) of the main cylindrical body portion 6 and is bolted to the base of the toilet.
A significant problem faced by plumbers during installation of the toilet is aligning the toilet fastening bolts 9 with the holes in the base of the toilet since the bolts are non-fixedly mounted to the toilet flange. Each fastening bolt, as shown in FIG. 3, is typically held in place with a plastic push-on bolt stabilizer (such as that disclosed in U.S. Pat. No. 7,950,886) which are slipped-down the toilet fastener bolt 9 to assist it in standing erect relative to the flange. The conventional toilet fastening bolts 9 are non-fixedly mounted for three reasons. The first is that the circumferential slots 2, which are most typical, allow for circumferential adjustment 10 of the bolts and thus the toilet as it is being lowered onto the flange. This provides a method to make sure the back of the toilet is set parallel to the nearest finished wall providing the most pleasing appearance. The second reason the toilet fastening bolts 9 are non-fixedly mounted, and thus loose fitting, is that if the toilet installer hits the fastening bolts during installation he may either chip the porcelain on the toilet base, bend the toilet fastening bolt or crack the toilet flange if the bolts were rigidly mounted. It is not uncommon for a toilet installer to knock-loose the fastening bolts 9 as he is lowering the toilet onto the wax ring (not shown) and toilet flange because the push-on bolt stabilizer is pliable and the toilet fastening bolt itself is not fixed relative to the slot 2. Once the toilet is set against the wax ring it generally cannot be removed without the possibility of future leakage. The third reason is that there are currently code requirements in some jurisdictions that dictate a design with the ability to service/replace the entire bolt assembly.
A further problem continually faced by plumbers involves the prevention of clogging of toilet drain pipes during construction due to the fact that the toilet flanges are mounted to the plumbing riser pipes long before the toilet is installed. Saw dust, fasteners, woodchips, tile, adhesives and various other construction debris fall into the drain pipe riser and cause major blockage after the newly completed building is occupied. Plumbers are known to use cloth, plastic, tape or a combination thereof as temporary covers or plugs in the riser pipe and toilet flange during construction. However these temporary plugs, such as a gathered rag, also capture debris and as they are removed it is common for construction debris to still make its way into the pipe riser. Furthermore, plumbing codes require either a liquid fill test or pressure testing of the drain system at the time of rough-in inspection to detect leaks. Therefore, it is necessary to provide access to the riser drain pipe to fulfill the testing requirement for rough-in inspection approval. Mechanical and nomadic test plugs are also quite often used to run the test. A recent proposed modification to toilet flanges to prevent debris has been to incorporate a knock-out plate 8 in the flange riser opening (FIG. 1). However, these knock-out plates 8 have shattered at the time of removal thus themselves become debris which may fall down the drain pipe. Also once the frangible connection of the knock-out plate is broken the shattered plate can no longer seal the pipe and cannot be reinstalled. To perform the code-required liquid fill test or a pressure test the knock-out would need to be removed so that water can be added to the riser pipe. The rough-in plumbing test conventionally requires a visual inspection of the water level, to make sure it remains unchanged, after 24 hours. Only if the water level is unchanged can it be verified that water leakage is not occurring in the system. If the riser pipe is left open after the rough-in plumbing inspection test then additional debris can find its way into the riser pipe once again during tiling work, which takes place after the test.
Another issue with conventional toilet flanges 1 is that they require a fastening assembly for securing the toilet to the flange which includes at least a pair of toilet fastening bolts, nuts, washers as well as a pair of push-on bolt stabilizers. These fastening elements of bolts, nuts, washers and bolt stabilizers are separate loose elements. Since they are loose elements they are either purchased separately or sold with the flanges and stored. If they are purchased with the flange it is not unusual for some or all of these stored fastening elements to go missing during the construction phase since it is usually months between the time the flange is installed and when the fastening elements are needed to secure the toilet.
Yet another issue with conventional toilet flanges is that they are designed with multiple keyed slots 2/5 for the toilet fastening bolts to fit into, in excess of just the pair needed, and this weakens the integrity of the flange. It is conventional to have the toilet flanges circular in design wherein the only considerations for orientation about the riser pipe are the keyed slot locations 2/5 for the toilet fastening bolts 9 and the positioning of the fastening apertures 12 to secure the flange to the floor. When mounting the toilet flanges on wood floors, it is best if the fastening apertures 12 for the flange can be oriented directly above floor joists so that the wood screws that secure the flange to the floor also bite into the floor joists beneath the plywood flooring.
Another issue with conventional toilet flanges, especially those without knockout plates, is that the center of the riser is not clearly identified although this measurement is critical in spacing the center of the toilet flange relative to the closest finished wall surface. Most toilets need to be spaced either twelve or fourteen inches from the centerline of the toilet flange or riser pipe to the finished wall surface.